Method and device for feeding granular powder

ABSTRACT

Provided is a method for feeding a granular powder from a granular powder feeding hopper onto an upper surface of a sheet material. A feeding passage is disposed so as to extend downward from an outlet of the granular powder feeding hopper so that the lower end of the feeding passage faces the upper surface of the sheet material moving beneath the feeding passage. The feeding passage is opened and closed by the open-close means so that the granular powder is intermittently fed from the granular powder feeding hopper onto the sheet material.

TECHNICAL FIELD

The present invention relates to feeding a granular powder, and morespecifically, to a method and a device for feeding a granular powderthat allow easy handling of the granular powder in the feeding thereof,and that are capable of feeding the granular powder intermittently ontoan upper surface of a sheet material.

BACKGROUND ART

Disposable wearable goods such as disposable diapers and the like aretypically provided with an absorber for absorbing liquids such as urineand the like. Among the absorbers are those provided with a granularpowder of a highly absorptive resin (Super Absorbent Polymer,hereinafter occasionally referred to as SAP) to absorb liquidsefficiently.

Conventionally, as a device that is used in the production of a granularpowder-containing sheet containing a granular powder between two sheetmaterials and that feeds a granular powder into container rooms formedin one sheet material, there has been a proposal on a device providedwith a roller-shaped transfer device (see, for example, PatentLiterature 1).

The conventional granular powder feeding device has, on thecircumferential surface of the transfer device, a plurality of recessedportions formed in a predetermined pattern. The transfer device isdisposed close to and beneath an outlet of a powder feeding hopper,facing, at a receiving position beneath the transfer device, a carriersupporting means that supports and transports the sheet material. Apredetermined amount of a granular powder fed from the granular powderfeeding hopper is received in each of the recessed portions on thecircumferential surface of the transfer device, and then is transferred,at the receiving position, from the respective recessed portions of thetransfer device into the container rooms in the sheet material supportedby the carrier supporting means.

CITATION LIST Patent Literature

-   PTL 1: Japanese Unexamined Patent Application Publication No.    2008-508052

SUMMARY OF INVENTION Technical Problem

In the conventional production apparatus, the granular powder is firstreceived in the recessed portions on the circumferential surface of thetransfer device, transferred to the receiving position, and thentransferred into the container rooms in a sheet material. In thisconfiguration, problems are that complicated devices are needed forhandling the granular powder and that the granular powder is not easy tohandle, for example, is likely to spill out of each of the devices.

Also, since the granular powder-containing sheet is, after having beenproduced continuously, cut into unit lengths suitable for use indisposable wearable goods or the like and separated, container rooms atportions where the cutting is made preferably do not contain thegranular powder. However, in the granular powder feeding device, thegranular powder is moved, being contained in the recessed portions ofthe roller-shaped transfer device, from the outlet of the powder feedinghopper to the receiving position, and therefore intermittent feeding ofthe granular powder to the container rooms formed in the sheet materialis problematically difficult.

The present invention is directed to solving the technical problems, andtherethrough to providing a method and a device for feeding a granularpowder that allow easy handling of the granular powder in the feedingprocess and that are capable of feeding the granular powderintermittently onto an upper surface of a sheet material.

Solution to Problem

In order to solve the problems, the present invention, when explained,for example, based on FIG. 1 to FIG. 9 that show embodiments of thepresent invention, is constituted as follows.

That is, Aspect 1 of the present invention relates to a method forfeeding a granular powder (6) from a granular powder feeding hopper (11)onto an upper surface of a sheet material (4), the method comprising:disposing a feeding passage (12) extending downward from an outlet (26)of the granular powder feeding hopper (11) so that the lower end of thefeeding passage (12) faces the upper surface of the sheet material (4)moving beneath the feeding passage (12); opening and closing the feedingpassage (12) with an open-close means (13); and thereby intermittentlyfeeding the granular powder (6) from the granular powder feeding hopper(11) onto the sheet material (4).

Aspect 2 of the present invention relates to a device for feeding agranular powder, comprising: a granular powder feeding hopper (11) forstoring a granular powder (6) and sending out a predetermined amount ofthe granular powder (6) from an outlet (26); a feeding passage (12)disposed so as to extend downward from the outlet (26); and anopen-close means (13) disposed in the feeding passage (12) for openingand closing the feeding passage (12), the lower end of the passage (12)facing an upper surface of a sheet material (4) moving beneath thefeeding passage (12).

Since the granular powder is fed from the granular powder feeding hopperthrough the feeding passage and allowed to be received in the containerrooms, the granular powder is prevented from spilling out of theapparatus, and thus can be handled easily. Additionally, since thefeeding passage is opened and closed by the open-close means, part ofthe granular powder flowing in the feeding passage is excluded to theoutside of the feeding passage, and thus the granular powder isintermittently fed onto the upper surface of the sheet material.

The feeding passage has only to be disposed so as to extend downwardfrom the outlet of the granular powder feeding hopper, and may beslanted with respect to the perpendicular direction. However,preferably, the feeding passage is perpendicularly disposed because, inthis case, the granular powder can be smoothly guided downward due togravity.

The open-close means has only to be capable of opening and closing thefeeding passage, and any configuration, for example, one in which thefeeding passage is opened and closed by a passage switching member thatis disposed in the feeding passage and is capable of switching to acollecting passage may be employed. However, the open-close meanspreferably comprises an open-close member that opens and closes thefeeding passage by intersecting the feeding passage. With thisopen-close member, the feeding passage can be opened and closed surelyand quickly, and thus, part of the granular powder, that is, thegranular powder existing within a predetermined range in a feedingdirection can surely be excluded to the outside of the feeding passage,achieving a so-called sharp intermittent feeding, in which the boundarybetween a portion of the granular powder to be fed and a portion of thegranular powder to be excluded is clear. Also, the position at which theopen-close means is provided is not specified, and thus the open-closemeans may be provided, for example, at the upper end or the lower end ofthe feeding passage. However, the open-close means is preferablyprovided in the middle part of the feeding passage in the verticaldirection because, in this case, it is easy to secure the installationspace thereof.

The shape of the open-close member is not particularly limited; however,a thinner member, such as a plate-like one, is more preferred, becausesuch a thin member is less likely to disturb the flow of the granularpowder when intersecting the feeding passage. Also, the open-closemember has only to be capable of opening and closing the feedingpassage, and the measurements and shape thereof may vary depending onthe cross-sectional shape of the feeding passage. Moreover, anopen-close movement of the open-close member may be based on anyconfiguration.

However, on the sheet material, the granular powder is placed so as toextend in the width direction, for example, as to be received in each ofa plurality of container rooms formed in a row in the width direction.Therefore, the feeding passage is preferably formed to have a transversecross-sectional shape long in the width direction of the sheet materialso as to be capable of feeding the granular powder simultaneously over apredetermined range in the width direction.

In this case, the open-close member is preferably formed so as to belong in the width direction of the sheet material, and to intersect thefeeding passage in a direction orthogonal to the width direction of thesheet material, because thereby the feeding passage is opened and closedsimultaneously over its entire range in the width direction and hencesupply of the granular powder is started and halted simultaneously overa predetermined range of the sheet material.

Also, the open-close member may intersect the feeding passage from anydirection. However, the open-close member preferably intersects thefeeding passage diagonally from an upper part of one side of the feedingpassage to a lower part of the other side, because thereby the granularpowder spilling and falling from the feeding passage during theintersection is surely excluded to the outside of the feeding passage.

The feeding passage has only to be disposed so as to extend downwardfrom the outlet of the granular powder feeding hopper, and the shape andposition thereof are not particularly limited. However, at least part ofthe feeding passage at which part the opening and closing thereof isperformed by the open-close means is preferably enclosed by a casing sothat the granular powder spilling from the feeding passage due to theopen-close operation is received inside the casing and prevented fromspilling to the outside of the feeding device.

In this case, the granular powder received in the casing can bedischarged to the outside of the casing by any means. However, when adischarge means that depends on an air stream such as suction passage orthe like is used, there arises a risk that an air current occurs in thecasing and influences the granular powder flowing in the feeding passagedue to gravity and/or the like. Therefore, a mechanical discharge meansis preferably provided in the casing so that the granular powderspilling out of the feeding passage is discharged to the outside of thecasing by this mechanical discharge means. In this case, the unnecessarygranular powder can surely be excluded to the outside of the casing, andthere is no risk of influencing the granular powder flowing in thefeeding passage.

When discharged to the outside the casing by a mechanical dischargemeans, there is a risk that the granular powder is damaged by thedischarge means. To avoid this, the granular powder may be discharged tothe outside the casing by a discharge means using gravity, and wherenecessary, a suction by an air stream such as suction passage or thelike in combination. This configuration can prevent the damage to thegranular powder and allow reuse of the granular powder of good quality,and is therefore preferable. Regarding the occurrence of the air currentinside the casing caused by the suction, as the countermeasuresthereagainst, the volume of the inner space of the casing is increasedas much as possible to suppress the air current inside the casing and anair intake port is provided on the casing as described later. As theresult, the velocity of the air current will not become high and itsinfluence on the flow of the granular powder can be suppressed.

An intermittent feeding of the granular powder can be achieved by anopen-close member that intersects the feeding passage of the granularpowder and thereby opens and closes the feeding passage, but in such acase where the production apparatus is to be stopped or rested andattempt is made to halt the feeding of the granular powder, an immediateclosing of the feeding passage by a rotationally driven open-closemember is difficult because it is required to quickly stop theopen-close member rotating at a high speed, at the closing position. Tosolve this problem, is employed a configuration having two kinds ofopen-close members, namely a first open-close member and a secondopen-close member. During the normal operation of the productionapparatus, the feeding passage is opened and closed repeatedly by thefirst open-close member whereas in the case where the productionapparatus is to be stopped or rested, the feeding passage is closedimmediately and continuously by the second open-close member. Thus, anextremely efficient mode of operation of the production apparatus can beachieved.

An intermittent feeding of the granular powder can be achieved by anopen-close member that intersects the feeding passage of the granularpowder and thereby opens and closes the feeding passage. In this case,the open-close member for opening and closing the feeding passage ismoved preferably not at a constant speed, but at a decreased orincreased rotational speed while the feeding passage is closed ascompared to the speed thereof in the state where the feeding passage isopen. By such a decrease or increase of the rotational speed, the ratioof the length of a portion to which the granular powder is not fed andthe length of a portion to which the granular powder is fed can befreely set as required according to the changes in the rotational speed.

In the case where the feeding passage of the granular powder is dividedinto a plurality of separate passages arranged in a raw in the widthdirection, it is also possible to exclude part of the granular powderflowing in part of the separate passages to the outside of the feedingpassage by an appropriate excluding means (such as mechanical means,blow means using an air stream, suction means, or the like). As theresult, the ratio of the granular powder containing room portion in thegranular powder-containing sheet produced by the apparatus for producingthe granular powder-containing sheet can be appropriately changed asneeded.

Advantageous Effects of Invention

The present invention, being constituted and functioning as mentionedabove, has the following effects.

(1) Since the granular powder is fed from the granular powder feedinghopper through the feeding passage and allowed to be received in thecontainer rooms, the granular powder is prevented from spilling out ofthe apparatus, and thus can be handled easily.

(2) The granular powder placed on the upper surface of the sheetmaterial is covered with a second sheet material, and thereafter the twosheet materials are joined to each other at parts thereof surroundingthe granular powder to give a granular powder-containing sheet. Thegranular powder-containing sheet is, after having been producedcontinuously, cut into unit lengths suitable for use in disposablewearable goods or the like and separated. Since the feeding passage canbe opened and closed by the open-close means, the feeding of thegranular powder onto the upper surface of the sheet material can behalted by closing the feeding passage at portions to be cut.Accordingly, when the granular powder-containing sheet is cut, the spilland fall of the granular powder at the time of cutting can be prevented.In addition, rapid wear of and/or damage to the cutting blade can beprevented.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view of an apparatus for producing a granularpowder-containing sheet provided with a granular-powder feeding deviceaccording to Embodiment 1 of the present invention.

FIG. 2 is a cross-sectional view of a main part of the granularpowder-containing sheet produced by the apparatus according toEmbodiment 1 or Embodiment 2 of the present invention.

FIG. 3 is an enlarged cross-sectional view of a main part of theproduction apparatus according to Embodiment 1 of the present invention.

FIG. 4 is a cross-sectional view of an open-close device used in agranular powder feeding device according to Embodiment 1 of the presentinvention.

FIG. 5 is an explanatory drawing for a movement of an open-close memberaccording to Embodiment 1 of the present invention.

FIG. 6 is a schematic view of an apparatus for producing a granularpowder-containing sheet provided with a granular-powder feeding deviceaccording to Embodiment 2 of the present invention.

FIG. 7 is an enlarged cross-sectional view of a main part of theproduction apparatus according to Embodiment 2 of the present invention.

FIG. 8 a to FIG. 8 f are explanatory drawings for a link mechanism of anopen-close member according to Embodiment 2 of the present invention.

FIG. 9 is a top view showing an example of a granular powder-containingsheet according to Embodiment 2 of the present invention.

DESCRIPTION OF EMBODIMENTS

The present invention will be concretely described below based on thedrawings. It goes without saying that the present invention is notlimited to the embodiments described below, but can be modified orchanged in many ways within the technical scope of the presentinvention.

Embodiment 1

As shown in FIG. 1, an apparatus (1) for producing a granularpowder-containing sheet comprises: an anvil roller (2); a shaping roller(3) that faces the anvil roller (2); a first feeding means (5) thatfeeds a first sheet material (4) to the circumferential surface of theshaping roller (3); a granular powder feeding device (7) that feeds agranular powder (6) which is a highly absorptive resin (SAP); a secondfeeding means (9) that feeds a second sheet material (8) to acircumferential surface of the anvil roller (2); and a joining means(10) that faces the anvil roller (2) and joins the two sheet materials(4, 8) to each other.

Further, the granular powder feeding device (7) comprises: a granularpowder feeding hopper (11) that stores the granular powder (6); afeeding passage (12) that guides the granular powder (6) from thegranular powder feeding hopper (11) to an upper part of the anvil roller(2); and an open-close means (13) provided in a middle part of thefeeding passage (12) in the vertical direction. Here, in thisembodiment, the open-close means (13) is provided in the middle part ofthe feeding passage (12) in the vertical direction, but the position ofthe open-close means (13) is not limited thereto; for example, in otherembodiments, the open-close means (13) has only to be provided in thefeeding passage (12), and may be provided at an upper end portion or alower end portion of the feeding passage (12).

Then, using the production apparatus (1), is produced a granularpowder-containing sheet (15), as shown in FIG. 2, containing a granularpowder (6) in separated container rooms (14) between the first sheetmaterial (4) and the second sheet material (8). Here, in thisembodiment, explanation is made on a case where the granular powder isSAP, but the granular powder is not limited thereto; for example, inother embodiments, the granular powder may be one other than SAP, andmay be grains, a finer powder, or a fibrous material.

As shown in FIG. 3, a shaping position (16) is provided on thecircumferential surface of the shaping roller (3), and a receivingposition (17) and a joining position (18) are provided along thecircumferential surface of the anvil roller (2)in this order fromupstream in the rotational direction thereof.

Onto the circumferential surface of the shaping roller (3), the firstsheet material (4) is fed to an upstream side of the shaping position(16) by the first feeding means (5). The shaping roller (3) faces theanvil roller (2) at the shaping position (16), and the first sheetmaterial (4) is passed between the two rollers. The shaping roller (3)is provided with a plurality of protruding portions (19) on itscircumferential surface, whereas the anvil roller (2) is provided withrecessed portions (20) on its circumferential surface, and the recessedportions (20) mesh with the protruding portions (19) of the shapingroller (3). Also, a nip roller (21) is disposed so as to face theshaping roller (3).

The lower end opening of the feeding passage (12) of the granular powderfeeding device (7) faces the anvil roller (2) and faces, at thereceiving position (17), the container rooms (14) formed on the uppersurface of the first sheet material (4) passing through the receivingposition (17). In this regard, the lower end of the feeding passage (12)is preferably disposed close to the surface of the anvil roller (2).Although the distance between the lower end of the feeding passage (12)and the surface of the anvil roller (2) is determined depending on theamount of the granular powder (6) to be fed, the distance is preferablyat least equal to the thickness of the granular powder to be fed, thatis, for example, the depth (th) of the container rooms (14) shown inFIG. 2. On the other hand, if the distance between the lower end of thefeeding passage (12) and the surface of the anvil roller (2) isexcessively larger than the depth (th), the granular powder (6) fed fromthe feeding passage (12) is unfavorably likely to scatter about due to,for example, an air current resulting from the reduced pressure insidethe recessed portions (20) on the surface of the anvil roller (2), aswill be described later. To prevent such a disadvantage, the distancebetween the lower end of the feeding passage (12) and the surface of theanvil roller (2) is preferably 10 mm or less, and more preferably 5 mmor less.

The joining means (10) is formed of an ultrasonic welding device, andthe end of its horn is disposed so as to face the anvil roller (2) atthe joining position (18).

The second feeding means (9) is disposed so as to feed the second sheetmaterial (8) in between the receiving position (17) and the joiningposition (18).

Inside the anvil roller (2) is formed a suction passage (22), andthrough the suction passage (22), interiors of the recessed portions(20) are communicably connected to an evacuation device (23). By theevacuation device (23), interiors of the recessed portions (20) at leastwithin the range from the shaping position (16) to the joining position(18) are vacuumed.

Of the feeding passage (12), the part lower than the open-close means(13) has a side surface open to the external space so that the granularpowder (6) passing through the feeding passage (12) will not beadversely affected by the reduced pressure inside the recessed portions(20). Also, a baffle plate (24) is disposed between the open sidesurface of the lower part of the feeding passage (12) and the anvilroller (2). The baffle plate (24) prevents the air current caused by thereduced pressure and/or the like from unfavorably influencing thefeeding of the granular powder (6).

Further, a vacuum retention member (25), such as one made of aperforated metallic sheet, is provided along the circumferential surfaceof the anvil roller (2) so as to face an area from the receivingposition (17) to the feeding position of the second sheet material (8),and thereby the vacuumed state inside the recessed portions (20) passingthrough the area is appropriately maintained.

The granular powder feeding device (7) comprises an amount regulatingdevice (32) attached to an outlet (26) of the granular powder feedinghopper (11), and a predetermined amount of the granular powder (6) issent out downward from the outlet (26). The feeding passage (12) isdisposed so as to extend downward from the outlet (26). The granularpowder (6), being sent out from the amount regulating device (32)downward along the feeding passage (12), flows smoothly in the feedingpassage (12). The open-close means (13) disposed in the middle part ofthe feeding passage (12) in the vertical direction is provided with, asshown in FIG. 4 and FIG. 5, a plate-like open-close member (27) that isI-shaped in plan view. The open-close member (27), which intersects thefeeding passage (12), is capable of opening and closing the feedingpassage (12) and thereby excluding part of the granular powder flowingin the feeding passage (12) to the outside of the feeding passage (12).

As shown in FIG. 5, the transverse cross-sectional shape of the feedingpassage (12) is long in the width direction of the first sheet material(4). Also, the open-close member (27) is longer in the width directionof the first sheet material (4) than the width of the feeding passage(12) so as to be capable of closing the feeding passage (12), and isdriven in a direction orthogonal to the width direction of the firstsheet material (4) so as to intersect the feeding passage (12).Specifically, two positions of the open-close member (27) arerotationally driven via link arms (28) respectively, and with aquadruple link thus formed, the open-close member (27) is kept paralleland is unidirectionally rotated.

The feeding passage (12) having a transverse cross-sectional shape longin the width direction of the first sheet material (4) has only to belong in the width direction as a whole feeding passage (12), and may bedivided into a plurality of separate passages of which respective widthsare short. In this case, since the granular powder (6) divided into therespective separate passages is fed as it is from the lower end openinginto the container rooms (14), the granular powder (6) is uniformly fedover the entire width of the first sheet material (4). In particular, itis preferable that inlets at the upper ends of the respective separatepassages are provided with incoming amount changing means, such as guideplates or the like, so that the granular powder (6) sent out from theamount regulating device (32) is divided equally at the inlets of therespective separate passages, because, in this case, the granular powder(6) can be fed more uniformly over the entire width of the first sheetmaterial (4).

Also, the open-close member (27), as shown in FIG. 4, is driven so as todiagonally intersect the feeding passage (12) from an upper part of oneside of the feeding passage (12) to a lower part of the other side.

As shown in FIG. 4, the open-close means (13) is provided with a casing(29) that encloses part of the feeding passage (12) at which it isopened and closed, and the open-close member (27) is rotationally driveninside the casing (29). Inside the casing (29), at a lower part thereof,a mechanical discharge means (30), such as a screw transportation deviceas an excluding means, is provided, and a discharge passage (31) isformed at the lower part of the casing (29). Preferably, the volume ofthe inner space of the casing (29) is large enough in order to suppressthe influence of the air current occurring inside the casing (29) due tothe reduced pressure inside the recessed portions (20) on the surface ofthe anvil roller (2), on the flow of the granular powder. Even if suchan air current occurs, when the volume of the inner space of the casing(29) is large enough, the velocity of the air current will not becomehigh, so that its influence on the flow of the granular powder can besuppressed.

Next, a method for producing a granular powder-containing sheet usingthe production apparatus will be described.

A first sheet material (4) that is fed onto the circumferential surfaceof the shaping roller (3) by the first feeding means (5) is passed, atthe shaping position (16), between the shaping roller and the anvilroller (2), and thereby container rooms (14) are formed in the firstsheet material (4). Since the container rooms (14) are shaped by theprotruding portions (19) and the recessed portions (20) that mesh witheach other, the container rooms (14) with a predetermined shape can besurely formed even when the production is performed at a high speed. Theease of shaping of the first sheet material (4) depends on thethickness, the material, etc. thereof; however, since its shaping isgenerally easier in a heated state, a heating means is preferablyprovided in the shaping roller (3) or its proximity. The heating meansmay be, for example, a heating device provided inside the shapingroller, a hot-air blower that blows heated air to the first sheetmaterial (4), or the like. The first sheet material (4) is transported,on the circumferential surface of the anvil roller (2), downstream inthe rotational direction thereof with the container rooms (14) suckedand held in the recessed portions (20) due to the reduced pressureinside the recessed portions (20).

In the process of the transportation, when the container rooms (14)reach the receiving position (17), the granular powder (6) fed from thegranular powder feeding hopper (11) through the feeding passage (12) isallowed to be received in the container rooms (14). At this time, sincethe transverse cross-sectional shape of the feeding passage (12) is longin the width direction of the first sheet material (4), the granularpowder (6) is simultaneously fed to and received in each of thecontainer rooms (14) arranged in a row in the width direction of thefirst sheet material (4). In this case, as described above, when thedistance between the lower end of the feeding passage (12) and thesurface of the anvil roller (2) is equal to or more than the thicknessof the granular powder to be fed, that is, equal to or more than thedepth (th) of the container rooms (14) shown in FIG. 2 and 10 mm orless, the granular powder (6) fed from the feeding passage (12) can beprevented from scattering about due to, for example, an air currentresulting from the reduced pressure inside the recessed portions (20) onthe surface of the anvil roller (2).

Thus, when the lower end of the feeding passage (12) is close to thesurface of the anvil roller (2) and the distance to the container rooms(14) is short, the granular powder falling from the feeding passage (12)is allowed to be efficiently received in intended container rooms. Thatis, as the result of the short distance between the lower end of thefeeding passage (12) and the surface of the anvil roller (2), thegranular powder (6) intermittently fed via the open-close member (27) isallowed to be efficiently received in intended container rooms (14)without scattering about when the feeding passage (12) is opened, and isstopped from flowing into corresponding container rooms (14) when thefeeding passage (12) is closed. Consequently, the state with the feedingpassage (12) closed by the open-close member (27) and the state with thefeeding passage (12) open after the open-close member (27) hascompletely finished traversing the feeding passage (12) are clearlyseparated, achieving a so-called sharp intermittent feeding of thegranular powder.

The first sheet material (4) is further transported, and when thecontainer rooms (14) reach the feeding position of the second sheetmaterial (8), the container rooms (14) are covered with the second sheetmaterial (8). The two sheet materials (4, 8) in a superposed state arefurther transported, and when the container rooms (14) reach the joiningposition (18), the two sheet materials (4, 8) are joined to each otheron the peripheries of the container rooms (14) by ultrasonic welding asthe joining means (10) described above.

In the feeding of the granular powder (6) to the container rooms (14),with use of the open-close member (27) of the open-close means (13) foropening and closing the feeding passage (12), part of the granularpowder flowing in the feeding passage (12) is excluded to the outside ofthe feeding passage (12); thereby the granular powder (6) isintermittently fed from the granular powder feeding hopper (11) into thecontainer rooms (14).

That is, when the rotationally driven open-close member (27) intersectsthe middle part of the feeding passage (12) in the vertical direction,the feeding passage (12) is closed. The granular powder (6) blockedduring this period by the open-close member (27) in the feeding passage(12) is excluded to the outside of the feeding passage (12), and thefeeding of the granular powder (6) to the container rooms (14) ishalted. Then, when the open-close member (27) has completely finishedtraversing the feeding passage (12) and gets out of the feeding passage(12), the blockage is released, and hence the feeding of the granularpowder (6) into the container rooms (14) is resumed. Thus the granularpowder (6) is intermittently fed downward into the container rooms (14).

Since the open-close member (27) is longer in the width direction of thefirst sheet material (4) than the width of the feeding passage (12) andintersects the feeding passage (12) in a direction orthogonal to thewidth direction of the first sheet material (4), the opening and closingof the feeding passage (12) is achieved at the same time over the entirewidth thereof. Therefore, the feeding of the granular powder (6) to therespective container rooms (14) arranged in a row in the width directionof the first sheet material (14) is simultaneously started andsimultaneously halted.

As the result, the granular powder-containing sheet (15) produced usingthe production apparatus has parts formed at predetermined intervalswhere none of the container rooms in a row in the width directioncontain the granular powder (6). Accordingly, when the granularpowder-containing sheet (15) continuously produced is cut into unitlengths suitable for use in disposable wearable goods or the like,cutting the granular powder-containing sheet (15) at the parts notcontaining the granular powder (6) can prevent the spill and fall of thegranular powder at the time of cutting, and can also prevent rapid wearof and/or damage to the cutting blade.

The open-close member (27) may be moved back and forth between one sideand the opposite side of the feeding passage, or moved so as todiagonally intersect the feeding passage (12) from a lower part of oneside to an upper part of the other side; however, preferably, as shownin FIG. 4, the open-close member (27) is driven so as to diagonallyintersect the feeding passage (12) from an upper part of one side of thefeeding passage (12) to a lower part of the other side. As the result,the granular powder (6) spilling and falling from the feeding passage(12) during the intersection is surely excluded to the outside of thefeeding passage (12). Since the part of the feeding passage (12) openedand closed by the open-close member (27) is enclosed by the casing (29),the granular powder (6) spilling from the feeding passage (12) due tothe open and close operation is caught inside the casing (29) withoutspilling to the outside. The granular powder (6) caught inside thecasing (6) is collected to the lower part of the casing (29), and isdischarged from the discharge passage (31) to the outside of the casing(29) by the mechanical discharge means (30).

Embodiment 2

To components common between the drawings used in Embodiment 2 and FIG.1 to FIG. 5, the same reference numbers are assigned, and explanationsfor the common components will be omitted here.

FIG. 6 is a schematic drawing of an apparatus for producing a granularpowder-containing sheet provided with a granular-powder feeding deviceaccording to Embodiment 2 of the present invention.

In Embodiment 2, as in Embodiment 1, an apparatus (1 a) for producing agranular powder-containing sheet comprises: an anvil roller (2); ashaping roller (3); a first feeding means (5) that feeds a first sheetmaterial (4); a granular powder feeding device (7) that feeds a granularpowder (6) which is a highly absorptive resin (SAP); a second feedingmeans (9) that feeds a second sheet material (8); and a joining means(10) that joins the two sheet materials (4, 8) to each other.

Receiving Position

As in Embodiment 1, a receiving position (17 a) and a joining position(18) are provided along the circumferential surface of the anvil roller(2) in this order from upstream of the rotational direction thereof;however, Embodiment 2 is different from Embodiment 1 in that thereceiving position (17 a) is located downstream of the top of the anvilroller (2) with respect to the rotational direction.

As shown in FIG. 1 and FIG. 3, in Embodiment 1, the receiving position(17) is located upstream of the top of the anvil roller (2) with respectto the rotational direction. Therefore, as will be described below,there is a risk that the granular powder (6) fed from the feedingpassage (12) is not received in intended container rooms (14) but spilltoward the upstream side with respect to the rotational direction.

After reaching the anvil roller (2), the granular powder (6) fed fromthe feeding passage (12) moves downward along the circumferentialsurface of the anvil roller (2) due to gravity, regardless of thereceiving position (17 or 17 a) on the anvil roller (2).

At this time, if the receiving position (17) is located upstream of thetop of the anvil roller (2) with respect to the rotational direction, asshown in FIG. 1 and FIG. 3, since the direction of the movement of thegranular powder (6) on the anvil roller (2) is opposite to therotational direction of the anvil roller (2), the granular powder (6) isnot smoothly received in intended container rooms (14), and is likely tospill into different container rooms (14) on the upstream side of therotational direction.

In Embodiment 2, as shown in FIG. 6 and FIG. 7, the receiving position(17 a) is located downstream of the top of the anvil roller (2) withrespect to the rotational direction. Since the direction of movement ofthe granular powder (6) on the anvil roller (2) is the same as therotational direction of the anvil roller (2), the granular powder (6) issmoothly received in intended container rooms (14).

The receiving position (17 a) in FIG. 6 and FIG. 7 is, as shown in FIG.7, located within a range of angle (α°) of 30° to 60°, preferably 40° to50°, toward the downstream side in the rotational direction with respectto a perpendicular line connecting the center of the anvil roller (2) tothe top thereof.

Means for Discharging Granular Powder in the Casing

When discharged outside the casing by a mechanical discharge means,there is a risk that the granular powder is damaged by the dischargemeans. To avoid this, in Embodiment 2, the granular powder is dischargedoutside the casing by a discharge means using gravity, and wherenecessary, a suction by an air stream such as suction passage or thelike in combination. This configuration can reduce the damage to thegranular powder and allow reuse of the granular powder of good quality,and is therefore preferable.

Regarding the occurrence of the air current inside the casing caused bythe suction, as the countermeasures thereagainst, the volume of theinner space of the casing is increased as much as possible to suppressthe air current inside the casing and an air intake port is provided onthe casing, as described above. As the result, the velocity of the aircurrent will not become high and its influence on the flow of thegranular powder can be suppressed. For example, as shown in FIG. 6, anair intake port (40) is provided on the casing (29) and a discharge duct(36) connected to a vacuum source (not shown) is attached to the lowerpart of the casing (29). By returning the granular powder (6) sucked bythe discharge duct (36) back to the granular powder feeding hopper (11),the granular powder (6) can be reused.

Shape of Open-Close Member

The open-close member (27) of Embodiment 1 is, as shown in FIG. 5,plate-like and generally I-shaped in plan view, whereas the open-closemember (27 b) of Embodiment 2 is, as shown in FIG. 8, nearly L-shaped inplan view. As shown in FIG. 8, two positions of the near L-shapedopen-close member (27 a) are rotationally driven via link arms (28 a)respectively, and with a quadruple link thus formed, the near L-shapedopen-close member (27 a) is kept parallel and is unidirectionallyrotated. The near L-shaped open-close member (27 a) is driven in adirection orthogonal to the width direction of the first sheet material(4) so as to diagonally intersect the feeding passage (12) of thegranular powder (6) from an upper part of one side of the feedingpassage (12) to a lower part of the other side by a repeated motion ofFIG. 8 a→FIG. 8 b→FIG. 8 c→FIG. 8 d→FIG. 8 e→FIG. 8 e→FIG. 8 f, thatopens and closes the feeding passage (12). Also, in pursuit of highspeed operation, the open-close member (27 a) employs a honeycombedstructure having a large number of hollows (41) therein for weightreduction without impairment of its strength. In this embodiment, asingle piece of the open-close member (27 a) is rotated, but theconfiguration is not limited thereto, and for example, in anotherembodiment, a plurality of pieces of the open-close member (27 a) may beused and alternately rotated for opening and closing the feeding passage(12) at a higher speed.

Use of a Plurality of Open-Close Members

An intermittent feeding of the granular powder (6) can be achieved by anopen-close member that intersects the feeding passage (12) of thegranular powder (6) and thereby opens and closes the feeding passage,but in such a case where the production apparatus is to be stopped orrested and attempt is made to halt the feeding of the granular powder(6), an immediate closing of the feeding passage (12) by a rotationallydriven open-close member is difficult because it is required to quicklystop the open-close member rotating at a high speed, at the closingposition. To solve this problem, as shown in FIG. 6 and FIG. 7, isemployed a configuration in which a second open-close member (38) isprovided apart from the first open-close member (27 a). During thenormal operation of the production apparatus, the feeding passage (12)is opened and closed repeatedly by the first open-close member (27 a) soas to intermittently feed the granular powder (6) whereas in the casewhere the production apparatus is to be stopped or rested, the feedingpassage is closed immediately and continuously by the second open-closemember (38). Thus, stopping and starting the feeding of the granularpowder (6) can be achieved in a manner suitable for the mode ofoperation of the production apparatus.

Whereas the first open-close member (27 a) is kept parallel and isunidirectionally rotated, as stated above, with a quadruple linkmechanism, the second open-close member (38) is coupled to a rod of anair cylinder (not shown) so as to be capable of reciprocating motion ina direction parallel to the plane of the paper and intersecting thefeeding passage (12). The second open-close member (38) is retreated tosuch a position as not to obstruct the flow of the granular powder (6)in the feeding passage (12) while the production apparatus is operated;however, when the feeding of the granular powder (6) is intended to bestopped as in a case where the production apparatus is to be stopped,rested, etc., the rod of the air cylinder can be extended to advance thesecond open-close member (38) to the position shown by the broken linein FIG. 7, so that the second open-close member (38) thus closes thefeeding passage (12) immediately and continuously to stop the feeding ofthe granular powder.

Speed Control of the Open-Close Member

An intermittent feeding of the granular powder (6) can be achieved by anopen-close member that intersects the feeding passage (12) of thegranular powder (6) and thereby opens and closes the feeding passage. Inthis case, the open-close member for opening and closing the feedingpassage (12) is moved preferably not at a constant speed, but at adecreased or increased rotational speed while the feeding passage (12)is closed as compared to the speed thereof in the state where thefeeding passage (12) is open. By such a decrease or increase of therotational speed, the ratio of the length of a portion to which thegranular powder (6) is not fed and the length of a portion to which thegranular powder (6) is fed can be freely set as required according tothe changes in the rotational speed.

For example, in FIG. 6, with use of a motor provided with an invertercontrol mechanism or, more preferably, a programmable servomotor, as theelectric motor (37) that rotationally drives the open-close member (27a), the ratio of the length of a portion to which the granular powder(6) is not fed and the length of a portion to which the granular powder(6) is fed can be freely set as required by changing the rotationalspeed of the open-close member (27 a) partially within one revolutionthrough a sophisticated control of the electric motor (37).

Ratio of Granular Powder Containing Room Portion

In the case where the feeding passage (12) of the granular powder (6) isdivided into a plurality of separate passages of which respective widthsare short, it is also possible to exclude the granular powder (6) thatis flowing in part of the separate passages to the outside of thefeeding passage (12) by an appropriate excluding means (such asmechanical means, blow means or suction means using an air stream or thelike, etc.). As the result, the ratio of the granular powder containingroom portion in the granular powder-containing sheet produced by theapparatus for producing the granular powder-containing sheet can beappropriately changed as needed. For example, as shown in FIG. 7, a blowduct (39) as the excluding means communicably connected to a pressurizedair source (not shown) may be attached to either side (at a most lateralposition in the width direction) of the feeding passage (12) so thatpart of the granular powder (6) flowing in the outermost passages in thewidth direction is intermittently blown off to be excluded to theoutside of the feeding passage (12). In this way, it is possible tonarrow, partially in the length direction in the granularpowder-containing sheet (15), the portion in which the container rooms(14) contain the granular powder (6). Here, the ratio of the granularpowder containing room portion can be adjusted to the shape of the humanbody by changing the degree of blowing off with use of the blow ducts(39).

Feeding Position of the Second Sheet Material

The second sheet material (8) is fed, as shown in FIG. 6 and FIG. 7, ata position that is on the downstream side of the receiving position (17a) in the rotational direction of the anvil roller (2) and is as closeas possible to the receiving position (17 a). Therefore, in Embodiment2, there is no vacuum retention member, such as the perforated metallicsheet, between the receiving position (17 a) and the feeding position ofthe second sheet material (8). Since the container rooms having receivedthe granular powder (6) are immediately covered with the second sheetmaterial (8), the granular powder (6) is prevented from being scatteredaround the apparatus. Guide member for the second sheet material

As shown in FIG. 6 and FIG. 7, a guide panel (33) is provided as asecond feeding means (9) for guiding the second sheet material (8). Thefront edge of the guide panel (33) is disposed at a position as close aspossible to the receiving position (17 a) so that, specifically, thelength obtained by subtracting the thickness of the second sheetmaterial from the distance between the receiving position and thefeeding position is 5 mm or less, and more preferably 2 mm or less. InEmbodiment 1 shown in FIG. 1 and FIG. 3, since the second sheet material(8) is fed onto the circumferential surface of the anvil roller (2) bythe second feeding means (9) using the guide roller system, a relativelylarge installation space is required. In contrast, by employing aguiding method with use of the guide panel (33), the installation spacecan be reduced, the front edge of the guide panel (33) can be disposedas close as possible to the receiving position, and moreover, thestructure of the equipment can be simplified because, without any rotarymember such as a roll, there is no need to take into account the failurethereof, etc. Also, since the guide panel (33) is disposed between thesecond sheet material (8) that is guided to the feeding position and theanvil roller (2), the second sheet material (8) is smoothly fed withoutbeing influenced by the reduced pressure on the surface of the anvilroller (2). Additionally, the guide panel (33) is preferably formed of amaterial having a smooth surface and a good wear resistance, forexample, stainless steel or ceramics.

Position of the Guide Panel

As shown in FIG. 6 and FIG. 7, the guide panel (33) is disposed so as tolie along a bottom face of the open-close means (13 a). By narrowing thespace between the open-close means (13 a) and the guide panel (33), theair current caused by the reduced pressure inside the recessed portions(20) on the surface of the anvil roller (2) is reduced and hence adisorderly movement of the granular powder (6) due to the air current issuppressed, leading to smooth flow of the granular powder (6) from thefeeding passage (12) to the container rooms (14).

Position of the Shaping Roller

The shaping roller (3) is disposed as close as possible to the receivingposition (17 a). By shortening the distance between the shaping roller(3) and the receiving position (17 a), it is possible to reduce thevolume of the space under a reduced pressure in the anvil roller (2), totransport the first sheet material (4), on the circumferential surfaceof the anvil roller (2), downstream in the rotational direction with thecontainer rooms (14) surely sucked and held in the recessed portions(20), and to reduce the energy cost, leading to low cost operation.

Vacuum Retention Member

The vacuum retention member (25), such as perforated metallic sheet orthe like, is disposed outside the first sheet material (4), along thecircumferential surface of the anvil roller (2) so as to face an areafrom the shaping roller (3) to the receiving position (17 a). With sucha vacuum retention member, the first sheet material (4) can be firmlysucked and held on the surface of the anvil roller (2) due to thereduced pressure inside the recessed portions (20) on the surface of theanvil roller (2).

Evacuating Interiors of the Recessed Portions (20) on the Surface of theAnvil Roller (2)

Inside the anvil roller (2) shown in FIG. 6 and FIG. 7 is formed asuction passage similar to the suction passage (22) shown in FIG. 3.Also, suction ducts (34) and (35) formed on a side face of the anvilroller (2) are communicably connected to a vacuum source (not shown),and interiors of the recessed portions (20) are communicably connectedto the vacuum source via the suction passage that is formed inside theanvil roller (2) and via the ducts (34) and (35). By this vacuum source,at least interiors of the recessed portions (20) ranging from theshaping position (16) to the joining position (18) are vacuumed.

While the method and the device for feeding a granular powder have beendescribed in the above embodiments, the description is nothing more thanillustrative examples giving concrete forms to the technical thought ofthe present invention. Therefore, the shapes, structures, measurements,materials, production procedures, etc. of respective parts are notlimited to those shown in the embodiments, and can be modified invarieties of ways within the scope of claims of the present invention.

For example, in the above embodiments, the apparatus for producing apowder-containing sheet is provided with an anvil roller, but theconfiguration is not limited thereto. In other embodiments, for example,the invention is also applicable to an apparatus in which the sheetmaterial is transported in a horizontal direction by a conveyor belt orthe like.

Also, in the above embodiments, the container rooms are formedbeforehand in the sheet material and thereafter the granular powder isfed and received in the container rooms, but the configuration is notlimited thereto. In other embodiments, for example, a sheet materialthat moves beneath the feeding passage may be a flat sheet material notprovided with container rooms. In this case, this sheet material and thesecond sheet material can be joined to each other on peripheries of thegranular powder that is placed on the sheet material to give a granularpowder-containing sheet. Further, the joining of the two sheet materialsmay be performed with use of, other than the ultrasonic welding deviceused in the above embodiments, any joining means, such as a heatedroller, a roller for pressure gluing the sheet materials onto which anadhesive such as hot melt or the like is applied, etc.

Further, in the above embodiments, the feeding passage is disposedvertically and the open-close means as the excluding means is providedin the middle part of the feeding passage in the vertical direction, butthe configuration is not limited thereto. In other embodiments, forexample, the feeding passage may be provided so as to be slanted withrespect to the vertical direction, and the open-close means may beprovided at the upper end or the lower end of the feeding passage.

Further, in the above embodiments, the spilt granular powder caught inthe casing is discharged to the outside of the casing by the mechanicaldischarge means, the gravity, or suction by an air stream, but theconfiguration is not limited thereto. In other embodiments, for example,other discharge means may be provided. Needless to say, the shape,driving method, etc. of the open-close member are not limited to thosedescribed in the above embodiments.

INDUSTRIAL APPLICABILITY

The method and the device for feeding a granular powder of the presentinvention allow easy handling of a granular powder in the feedingthereof, and are capable of feeding the granular powder intermittentlyonto an upper surface of a sheet material, and therefore, are useful, inparticular in the production of absorbers used for disposable wearablegoods, and also in the production of other products using a granularpowder.

REFERENCE SIGNS LIST

-   1, 1 a apparatus for producing a granular powder-containing sheet-   2 anvil roller-   3 shaping roller-   4 sheet material (first sheet material)-   5 first feeding means-   6 granular powder-   7 granular powder feeding device-   8 second sheet material-   9 second feeding means-   10 joining means-   11 granular powder feeding hopper-   12 feeding passage-   13, 13 a open-close means-   14 container room-   15 granular powder-containing sheet-   16 shaping position-   17, 17 a receiving position-   18 joining position-   19 protruding portion-   20 recessed portion-   21 nip roller-   22 suction passage-   23 evacuation device-   24 baffle plate-   25 vacuum retention member-   26 outlet of the powder feeding hopper (11)-   27, 27 a open-close member-   28, 28 a link arm-   29 casing-   30 mechanical discharge means-   31 discharge passage-   32 amount regulating device-   33 guide panel-   34 suction duct-   35 suction duct-   36 discharge duct-   37 electric motor-   38 second open-close member-   39 blow duct (second excluding means)-   40 air intake port-   41 hollow

1. A method for feeding a granular powder from a granular powder feedinghopper onto an upper surface of a sheet material, the method comprising:disposing a feeding passage extending downward from an outlet of thegranular powder feeding hopper so that the lower end of the feedingpassage faces the upper surface of the sheet material moving beneath thefeeding passage; opening and closing the feeding passage with anopen-close means; and thereby intermittently feeding the granular powderfrom the granular powder feeding hopper onto the sheet material.
 2. Themethod for feeding a granular powder of claim 1, wherein the open-closemeans is provided with an open-close member that opens and closes thefeeding passage by moving so as to intersect the feeding passage.
 3. Themethod for feeding a granular powder of claim 2, wherein the transversecross-sectional shape of the feeding passage is long in the widthdirection of the sheet material; the open-close member is formed so asto be long in the width direction of the sheet material; and theopen-close member is moved in a direction orthogonal to the widthdirection of the sheet material so as to intersect the feeding passage.4. The method for feeding a granular powder of claim 2, wherein theopen-close member is moved so as to diagonally intersect the feedingpassage from an upper part of one side of the feeding passage to a lowerpart of the other side.
 5. The method for feeding a granular powder ofclaim 2, wherein the moving speed of the open-close member intersectingthe feeding passage is different from the moving speed of the open-closemember in a state where the feeding passage is open.
 6. The method forfeeding a granular powder of claim 2, wherein the open-close means isfurther provided with a second open-close member so that the feedingpassage is opened and closed repeatedly by the open-close member, and asneeded, is continuously closed by the second open-close member.
 7. Themethod for feeding a granular powder of claim 1, wherein at least partof the feeding passage at which part the open-close means opens andcloses is enclosed by a casing so that the granular powder spilling fromthe feeding passage due to the open-close operation is received insidethe casing; and the received granular powder is discharged to theoutside of the casing by a discharge means.
 8. The method for feeding agranular powder of claim 1, wherein the feeding passage is divided intoa plurality of separate passages arranged in a row in the widthdirection of the sheet material; and part of the granular powder flowingin part of the separate passages is discharged to the outside of thefeeding passage by an excluding means so as to adjust the amount of thegranular powder fed from the granular powder feeding hopper onto thesheet material.
 9. A device for feeding a granular powder, comprising: agranular powder feeding hopper for storing a granular powder and sendingout a predetermined amount of the granular powder from an outlet; afeeding passage disposed so as to extend downward from the outlet; andan open-close means disposed in the feeding passage for opening andclosing the feeding passage, the lower end of the feeding passage facingan upper surface of a sheet material moving beneath the feeding passage.10. The device for feeding a granular powder of claim 9, wherein theopen-close means is provided with an open-close member that opens andcloses the feeding passage by moving so as to intersect the feedingpassage.
 11. The device for feeding a granular powder of claim 10,wherein the transverse cross-sectional shape of the feeding passage islong in the width direction of the sheet material; the open-close memberis formed so as to be long in the width direction of the sheet material;and the open-close member is moved in a direction orthogonal to thewidth direction of the sheet material so as to intersect the feedingpassage.
 12. The device for feeding a granular powder of claim 10,wherein the open-close member is moved so as to diagonally intersect thefeeding passage from an upper part of one side of the feeding passage toa lower part of the other side.
 13. The device for feeding a granularpowder of claim 10, further comprising a control mechanism that enablesthe moving speed of the open-close member intersecting the feedingpassage and the moving speed of the open-close member in a state wherethe feeding passage is open to be separately set.
 14. The device forfeeding a granular powder of claim 10, wherein the open-close meansfurther comprises a second open-close member so that the feeding passageis opened and closed repeatedly by the open-close member, and as needed,is continuously closed by the second open-close member.
 15. The devicefor feeding a granular powder of claim 9, wherein the open-close meanscomprises: a casing for enclosing at least part of the feeding passageat which part opening and closing is performed; and a discharge meansfor discharging the granular powder spilling from the feeding passageand caught inside the casing to the outside of the casing.
 16. Thedevice for feeding a granular powder of claim 9, wherein the feedingpassage is divided into a plurality of separate passages arranged in arow in the width direction of the sheet material; and an excluding meansis provided for discharging part of the granular powder flowing in partof the separate passages to the outside of the feeding passage so as toadjust the amount of the granular powder fed from the granular powderfeeding hopper onto the sheet material.